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Cited by 768

The DOI matches its Crossref record; 14 of the 14 references it cites were found in a registry or an index.

Observe locally, infer globally: A space-time MRF for detecting abnormal activities with incremental updates

Kim, Jaechul, Grauman, Kristen·2009·2009 IEEE Conference on Computer Vision and Pattern Recognition

Abstract

We propose a space-time Markov random field (MRF) model to detect abnormal activities in video. The nodes in the MRF graph correspond to a grid of local regions in the video frames, and neighboring nodes in both space and time are associated with links. To learn normal patterns of activity at each local node, we capture the distribution of its typical optical flow with a mixture of probabilistic principal component analyzers. For any new optical flow patterns detected in incoming video clips, we use the learned model and MRF graph to compute a maximum a posteriori estimate of the degree of normality at each local node. Further, we show how to incrementally update the current model parameters as new video observations stream in, so that the model can efficiently adapt to visual context changes over a long period of time. Experimental results on surveillance videos show that our space-time MRF model robustly detects abnormal activities both in a local and global sense: not only does it accurately localize the atomic abnormal activities in a crowded video, but at the same time it captures the global-level abnormalities caused by irregular interactions between local activities.

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Metadata

Authors
Kim, J., & Grauman, K.
Venue
2009 IEEE Conference on Computer Vision and Pattern Recognition
Publisher
IEEE
Published
2009-06
Pages
2921-2928
ISSN
1063-6919 (ISSN-L)
OpenAlex
W2138092272
Cited by
768
References
14
FWCI
12.93
Type
conference paper
Language
en
Open access
closed

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CoChat. (2026). Citation check: Observe locally, infer globally: A space-time MRF for detecting abnormal activities with incremental updates. https://app.cochat.ai/papers/10.1109/cvpr.2009.5206569
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Kim, J., & Grauman, K. (2009). Observe locally, infer globally: A space-time MRF for detecting abnormal activities with incremental updates. 2009 IEEE Conference on Computer Vision and Pattern Recognition. https://doi.org/10.1109/cvpr.2009.5206569

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